Motivated by building codes, national regulations, the general desire to save energy, and/or the like, some building designers, architects, and owners make calculations and predictions about building energy consumption. In general, it is desirable to reduce the energy a building consumes, thereby potentially reducing total occupancy costs (e.g., through lower heating and/or cooling costs), providing “greener” or more environmentally-conscious structures, etc.
Windows are bi-directional energy pathways in a building envelope and as such oftentimes have a large influence on the energy exchange balance between the building and its environment. Whether specifically marketed under the name “net zero energy buildings” or a like term, there is a trend towards the construction of buildings that use no more energy than they produce.
Given this background, so-called “smart windows” or glazings that are able to individually measure the heat energy flux traversing through them are starting to have a reason to exist. For instance, smart windows can in some instances allow lighting to be used more cost effectively through improved light management, cut down on the use of air-conditioning and heating through improved thermal management, etc. For instance, with respect to the former, switchable glazings (such as, for example, glazings incorporating polymer-dispersed liquid crystal (PDLC) materials, polymer-assembled liquid crystal (PALC) materials, electrochromic, electrochromic/photochromic hybrids, etc.) may be activated or deactivated to allow more or less light to pass into (or redirected through) a building. In order to achieve the latter, for example, it would be desirable to have information regarding the thermal flux through a building envelope, e.g., for localized and/or automatic temperature control and, thus, to make adjustments that have an impact on the overall building energy consumption.
In order to aid in achieving the above-identified and/or other aspects, it may be possible to integrate heat flux sensors into glazings. In this regard, the inventor of the instant application has observed that heat flux incident on a building envelope sets up a temperature field or spatial temperature gradient, both perpendicular and parallel to the glazing By measuring this temperature gradient (whether in a steady state or transient mode), it becomes possible to measure with a high accuracy the instantaneous heat flux through the window.
By simultaneously performing this measurement over several window locations on a building envelope or façade, one can compute the instantaneous net heat flux (or its time differential) passing in to or out of a building envelope with high precision. This information can be used to trigger many different actions such as, for example, dimming or brightening a switchable glazing, triggering localized heating or air-conditioning events in lieu of central functions, etc.
Such sensors may be small in size, possess power autonomy, and be integrated with relative ease into modern glazings. Such sensors also may be used in automotive applications (such as, for example, laminated in automotive sunroofs, windshields, etc.), refrigerator/freezer doors, etc. As such, they may be used to trigger automotive shades to be opened/closed to increase/decrease heat in the cabin of the vehicle, trigger cooling to help reduce the likelihood of food spoiling, etc.
In certain example embodiments of this invention, a glazing assembly including a first glass substrate is provided. A radiation shield covering, directly or indirectly, at least a part of a peripheral edge area of the first glass substrate. A dual junction solid-state heat flux sensor includes a first junction oriented in the assembly at a first location at which radiation from a radiation source is receivable through the first glass substrate; a second junction oriented in the assembly at a second location that is blocked from the radiation source by the radiation shield; and circuitry configured to generate a signal based on a differential between transduced voltages respectively generated at the first and second junctions.
According to certain example embodiments, a control module may be configured to receive the signal and selectively generate an action responsive thereto. For instance, the control module may be used to selectively trigger an action to be taken in a system external to the glazing and/or with respect to the glazing itself.
In certain example embodiments of this invention, a method of making a glazing assembly is provided. The method comprises: covering, directly or indirectly, at least a part of a peripheral edge area of a first glass substrate with a radiation shield; connecting a dual junction solid-state heat flux sensor to the first glass substrate, so that a first junction of the sensor is oriented in the assembly at a first location at which radiation from a radiation source is receivable through the glass substrate, and a second junction of the sensor is oriented in the assembly at a second location that is blocked from the radiation source by the radiation shield; and providing circuitry configured to generate a signal based on a differential between transduced voltages respectively generated at the first and second junctions.
Methods of using the glazings described herein also are provided in certain example embodiments.
The features, aspects, advantages, and example embodiments described herein may be combined to realize yet further embodiments.